Nowadays propagating patches to diverse IoT devices is not a simple task, especially considering that many IoT devices are designed to operate in unfavorable conditions, without reliable Internet access and without user assistance. Examples of these kinds of devices include home appliances, such as washing machines or fridges (sometimes referred to as white goods, because they are frequently white in color); low power connected home automation devices, such as motion sensors, door locks, window sensors; and automotive devices (cars and accessories).
Unfortunately, many “smart” devices are not necessarily always connected directly to the Internet due to the high power required for Wi-Fi connectivity, or not connected because consumers fear “hackers” or simply don't want to or are unable to connect them. At the same time, manufacturers want to patch these devices quickly, especially when critical vulnerabilities are discovered.
Even if the devices are online, propagating a patch to millions of devices can take a considerable amount of time and resources. In the event of a security-related critical patch, manufacturers want to propagate the patch as fast as possible, while at the same time reducing the resources consumption.